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metapirat
01-22-2002, 06:47 AM
Hi everybody,

i try to use the Histogram facilities of opengl 1.3. This is what im doing right now:

glHistogram(GL_HISTOGRAM, 2, GL_RGB,true);

glEnable(GL_HISTOGRAM);

// do some drawing here ...

// Reset Histogram:
glResetHistogram(GL_HISTOGRAM);
// copy the framebuffer on itself to trigger histogram evaluation

glRasterPos2f(0,0);
glCopyPixels(0,0,silhouette.width(), silhouette.height(), GL_COLOR);

glFlush();

unsigned int values[2];
glGetHistogram(GL_HISTOGRAM, GL_FALSE, GL_RED, GL_UNSIGNED_INT, values);

when i print out the values array, i just get two zero values.

i currently use an nvidia riva tnt and the latest linux driver, which implements opengl 1.3.

i am thankful for every kind of advice.
Thanks for your time and effort,

metapirat